Internal cylinder gate



Sept. 30, 1958 L.. R. Pls'roLs 2,853,789

INTERNAL CYLINDER GAGE v 1N VEN TOR. LAMBERT R. P/STOLES BY kgw ATTORNEYA R. PlsToLEs 2,853,789 INTERNAL CYLINDER GAGE:

2 Sheets-Sheet 2 INVENToR. LAMBERT IP PISTOLES- BY -Q nTTofa/vsv Sept. 30, 1958 Filed July 28, 1955 United States Patent INTERNAL CYLINDER GAGE Lambert R. Pistoles, Wilmington, Del.

Application July 28, 1955, Serial No. 524,997

8 Claims. (Cl. 33-178) This invention relates to gages, and more particularly to gages adapted to measure the internal diameter of cylindrical objects.

ln measuring the internal diameter of cylindrical objects, it is important that the measuring device be aligned with a diameter of the object. this respect results in the-measurement of a chordal distance less than the diameter, with consequent inaccuracy. In gaging cylindrical objects in mass production it is desirable to provide an indicator which may be quickly applied to the object for an indication, with assurance that the indication will be that of true internal diameter.

It is accordingly an object of the present invention to provide, in a gage `of the type described, a mechanism for assuring indications of true diameter.

It is further an object of the invention to provide in such a gage an arrangement whereby the gage may be utilized on a wide range of diameters, with like assurance of accuracy.

It is a further object of the invention to provide a gage which is composed of few parts, of rugged construction, and which may be readily set to gage a plurality of selected ranges of internal diameter measurements.

The above and'other novel features ofthe invention will appear more fully hereinafter from the following detailed description when taken in conjunction with the accompanying drawings.H lt is expressly understood that the drawings are employed for purposes of illustration only and are not designed as a definition of the limits of the invention, reference being hadfor this purpose to the appended claims.

In the drawings wherein like reference characters indicate like parts: 1

Figure l is an enlarged plan View with parts in section of one application of the gage;

Figure 2 is an enlarged sectional View of the gage shown in Figure l taken substantially on the line 2-2 of Figure 1;

Figure 3 is a side elevational view of the gage with an extension;

Figure 4 is a plan view with parts in section of the gage adapted for a range of larger `diameter measurements; l

Figure 5 is a plan view with parts in section, ofthe gage adapted for a still larger range of diameter measurements; and

Figure 6 is a fragmentary view partly in section of a vhandle'for the gage.

Referring to Figures 1-3 inclusivefthere is shown a gage lblock having a relatively xed contact pin` 22, agage actuating movable pin 24 aligned therewith and slidable in the bore 26 of the block, and adapted to pro- Lvide vaccurate diameter measurements when theaxes of lsaid pins are held on a'diameter of an internal cylindrical lWorkpiecesuch as 25. To assure centering ofthe gage piu 'on' 'a diameter, there are providedadjustable spring Failure to use care in Cfr Mice

2 plunger pins 28 and 30 laterally disposed on either sid of the contact and gage pins, in symmetrical arrangement. The block is provided with a circular recess 32 in which is positioned in a protected manner a dial indicator 34. The bottom of the recess has a raised circular deck 36, the latter being adapted to substitute for, and be received in place of the circular back plate of a stock dial indicator of the type shown. The dial indicator has a circular body or casing portion 38 having an annular shoulder 40 adapted to receive the raised deck 36, and the indicator is adapted to be held in place through screws such as 42 and 44, the heads of which are seated in the dial plate 46, and threaded in the raised deck 36. The construction is similar to that shown in my Patent No. 2,610,409 issued September 16, 1952.

The dial indicator shown includes the usual indicator rod 58, slidably positioned in apertured bosses 60 and 62. The rod has been reduced in length by removing a portion of the right hand end thereof as seen in Figure 2. The rod or pin is provided with rack teeth operating on a pinion 64, in turn actuating a dial hand 66 through the gear 68 and pinion 70. Slack take-up is provided by the gear '72 and hair spring 74, all as will be readily understood in the art. The rod is biased to move to the right by a tension spring 76 also connected to the casing 38, and movement of the rod is limited by the shoulder formed by the screw head 7 8.

The bearing plate 80 within the indicator is slotted as at 82, to provide access to the dial rod 58 and permit the rigid insertion into such rod 0f a ball head actuating pin 84. The pin has a reduced shank portion 86, and may be secured in the rod by any suitable means such as a driven or screw thread tit. The pin extends through an aperture 88 in the deck 36 to intersect the pin bore 26, and the ball head 90 is so located as to lie on the axis of the bore.

The gage pin 24 is provided with a concentric bore 92 extending from one end, which is threaded to receive threaded members in the form of a socket head set screw 94, and a locking screw 96. The pin is also slotted as by milling at 98 to permit the ball head and shank portion 86 to extend into the pin so that the ball head may bear against the transverse end surface of the socket head set screw 94. The slot 98 is of greater width than the shank diameter of the ball head pin.

A key screw 100 threaded into the block engages a slot 99 in the pin 24, and provides an outside limit for the pin movement, and prevents the pin from turning.

The locking screw 96 has an enlarged head 101 which lies within the enlarged diameter portion 102 of the bore 26, the head being adapted to limit movement of the pin to the left, as shown in Figure 2. The enlarged bore 102 is threaded and has positioned therein a split collar 106, having an inwardly directed spring seating flange 108. The enlarged head 101 and collar 106 provide opposed spring recesses for receiving the coil spring 110. The head 101 is provided with a screw driver slot 103 or other means for tightening the screw 96, and the collar 106 may be similarly provided as at 107. The split collar is of resilient material and is slightly contracted when threaded in place to provide a friction grip with the threads when set in place.

In the end of the bore, there is threaded a bushing 112 having an internally threaded bore 113 adapted to receive the shank of the xed pin 22, the pin being provided with an enlarged head, of hexagonal section as at 116, and is also provided with a recess 118 to receive a contact ball 120, the ball being adapted to engage the concentric conical seat 122, and being held in the recess by peening over the lip 124 of the recess. It will be understood that the ball is free to roll within the recess.

The opposite end of the Apin 24 .is similarly `provided with` a conical bottom recess 126, and a contact ball 128.

' The plunger pins 28 and 30 each comprise a body portion '130 lhaving a cylindrical exterior adapted to `freely slide Within ithe bore 132 :in 'the block 20. Each;pin vfis provided with ia 'contact ball 134 free to lroll yand to be held in a coaXial 'conical 'bottomed recess 13:15,v the lip '138 'being 'ip'eened over. The lpin is further provided kwith abore 140adapted to receive a calibrated coilspri'n'g i142, andan adjusting screw 5144, the latter being threaded fin a reduced'diameter lfex'tensionof the bore '132. The screw 144 is provided with an annular 'shoulder i146, one `face 'of which 'engages an "end of vthe'spring `=142,.and theiother face of 'which Lis adapted to be urged against 'a split'sprizng flock rring `)147 set 1in an internal iannular groeve @in the 'bo-'rie 140. Y Radial lapertui'es Ysuch 'as v148, intersecting the -g-'OOVe pTVd 1'ltf''il's 'I -u'ns'etig the --ltk ring 147. It will b e seen that eahof the `pins-Z8 and-3i) isfa'srially adjustablefinthei'rrespective blofckbfes-By threadin'gthe adjusnn f -reves-nga. thefserews arefsuitebiyae- 'A =`'2H-"e heldy by bfSS TI'JSCd Set SI'B'WS "s `-'150 threaded in the block 20. n

In practice, :with the sp'ring's i142 :of y'each "of fthe 'pins 28 and 30 alike, theplung'ers yare setfso fthat eac-h Yprojects 'fair equal 'distano-efrom the block, the `distance being lselectedin'a'cicorda'rice Withtheradius 'of curvature-of the ycylinder boretobe gaged When the gage is positioned 'in place, the lpirs Yaire each yieldingly `-rnoi/"ed Lirit'o their respective boi-es, and in-so doing -prvidean equalizing pressurel upon the surface to be rgag'edfsola'stofcausethe gaxisfof the gagepn to ycoincide 'with 4:a f diameter, y'or lie 1in VadiaIriet'rical plane 6i' -the lbore. By rocking t'heg'age, I-vvith the -v'airis `lying upo'n'the diametrica'l piane, Ma minihutn reading `3Wi1l appear on the Y"dial When-radial align- @nicht ioccurs, `Without -dn"g"r of errorby ir'eas'onb'f the g'ag'ef'a'xis `being located onla chordirs'teadof'a 'diameter yof theworkip'iece.

fs "shown in lFigure 3, the `gage 'may be provided With aahandle 152 mounted on a bracket 154 secured t'othe -Ablock 20. ils'o lthere `is shovvnlthe Agage :provided `with aheirtesion "-156 for'the vvcontact l22,V for 'accommodating fa'igre'a'ter rarigeof diameters. The'eXtensionlis Aprovided iwi-th v'vrench llats V1548, aridhs "a'bushingy end160 threaded 'inthe-block 20. The vther endis adapted to threadedly receive the Ashank 161 of lthe `emta'ct f22, a v lock nut 162 being p'rvided'theren 4 y fwhien-hev'e threaded sia-anke frise te Vextend inte the provided *with w'rienh ats 1.90, and iaireduceddiarneter 2,853,789 u A .l 'A i The shank.19 8as`we1l as .the extensions maybe of diler:

ent length so that a wide range of diameters can be a'ccommodated.

For still larger diameters, an extended bridge as shown o in Figure may be employed, and in order to locate the gage inwardly from the surface being gaged, the bridge is supported on extension members. As shown, the block 20 is provided with extensions `2'02 and 204, one end of which simulates the plunger assembly, and is adapted to be inserted into each of the bores 132 after removal of the assemblies. The extensions have Wr'e'nch ats 205 and a shoulder 206 Cadapted to `engage the :end `llace 208 of the block 20, and the threaded end 210 is received in the threaded block 'bore 212.v The other end of each extension is provided with a reduced diameter portion 213 received in a recess inthe bridge member 214, and is held to the bridge member by a screw such as 216. The gagepi'n `2.18 :is f-selected'o'f a flength to match itheeextem sions i202 'and z204, :and fis substituted for the shorterv pin 24. The rear Contact 22 can be set at any desired'di'stan'ce as by use of .fan Kextension member 222 -or members as described in Figure =4IorFigu'rle :3. ln fallrm'odification's ther-gage-andcontact/pins arecoaxial. f

To initially adjust the gage yfof l.Figure il., Vthe distance between the ftrue :planar surface l21, 'which :is at right Yanglestoltlrteiaxis ofthe'ga'ge pin 24, and eachf'of the :balls 134'of th'eplungers 228 andr30, 'are setrat y.equal distances byfa micrometer, when 'the plunger's are -freely'extended, the :adjustment being made bylthefsetting offscrews .144, and then locking the screws by tightening the setfscrews V1150. 11n the '-modilications of Figures `V4 'and A5, the block surface 119 is aftruegsurfacegparalll*with surfa'celyand the surfaces and.17tare1tr1e :planarlsurfacesgand'are likewise Imounted'parlleltolthesurface `119.v :The ends 1173 and f1-*75 of the @plunger housings .112 and 2174 {(s'e'e rEigure 4) 'are parall'el 'with :the fsurfac'e .17, and equally spaced therefrom. Similarly the ends 231 -and of lthe :plungerl housings 2230 :and .1232 vr(see Figure 5) `are parallel `with 'the surface `15, and ".equallyspaceltherevvfrom. #A thimble, lor :spacer cap x234,`fada`pted 5to freely Mtit' over-the :nut 3184 fand "seatl on :the ends S1173 'and .175, or 231 and 233 is placed in position, as indicatedifor =examp1e invFigure V5, `andthe-distance :hetweeneadh of the :plunger balls Aandlth'e :transverse ltrue :end 435 fof the cap "when @placed -on the :respective :housing is then fset *so @that 'fthe ldistance rbetween theasurfaces Maand-i175 andltheirespectiveplunger 'b1Is,:or-2311 and 233,1a'nd their 'fir-espective '.iplun'ger -balls :are equal. Th'ereupontheLnuts :1842are-tightened,' andthega'gerechecked.

A suitable handle for supporting t-lr'egagefrm'niex tension-sleeve suchas .1194? in Eigure4,:is1shwn LinFigure 6. A T tting 280 having a bore 282 toreceive theexftersi'on i194, lis provided ywith a 'b'orea'tlright :angles :thereto, which bore is internallythreaded'tasatlil'fo receive '-afhandle 236. Thefthreadedendloffthehandle i'sia'dapted @to bear f'against "a brass block v238-looselyheldA in place by a small pin 240 extending across the fitting, andlloosly thr'ough an Iaperture 242 inthe lblok-238. A tight "grip can thenbe had upon the extension 194, bytur-nin'g -the fhandlevand thereby applying pressure Atordrev bloc-kmh.

-It virili be seen that by the 4:arrangements .shown :in Figures 1 and 2, Figure 4, and Figure 5, that thebasic :gage biocktcanbe adapted tota pluralityao'f ranges by supplying bridgefparts rand v:extension member-eras. shown. In practice, it is essential to use a bridge ofsucient 'Width to'@ space the contacts 28 Sand :30 as widely Las 'possible, for va maximum centering effect. :Howeventlie Sangle fof the ltangent rdf fthe V4surface` being tested iat the ointfof-.contacti'mu'st 'riot'approach 'orexceed Ltheangieof 70 fith'e conical -b'allfsea'tszatlthebase'offthe recesses-1136,@since itf is Y'essentialYthat the' :ball be Lurgedltofseat-on the conical "seat, "with"'thed'naIl rcenter-on/the axisof the;plungcr while fthebllfisiineontacf'with the `cylindrical surface. illl'he .'apexangle 'of'the conical aisea't, if51-20degrees,-wvll;per 75 Smit lthe Aga,geflralu-ngeers"to contact internalfsurfaces iat essere@ points spaced less than 60 'degrees apart, and in practice at points spaced about 45 or somewhat less.vv The combined effect of each of the Contact balls 134 urges the gaging pin 24 to locate on a diameter by 'reason of the umform spring action of the calibrated springs 142, it being understood that due to the curvature at the point of ball contact, any misalignment will cause one ball contact to be moved inwardly, a greater increment than the other, because of the increasing angle of the tangent at the point of contact. Thus the calibrated springs will urge the points of contact of the contacts 28 and 30 to engage the surface at points the tangents of which have equal angles wih respect to the axis of the gage pin.

While several modiiications of the invention have been shown and described, it is' to be understood that the invention .is not limited thereto. As many variations in use and operation and changes in construction and arrangement may be made without departing from the spirit of the invention, as will be apparent to those skilled in the art, reference will be had to the appended claims for a definition of the limits of the invention.

What is claimed is:

1. A gage for measuring internal diameters comprising a gage block having an indicator mounted thereon, a settable pin mounted in said block and adapted to contact the internal wall of a cylindrical work object, a movable pin mounted in said block, and aligned with said settable pin, said movable pin having a contact end adapted to conta-ct the internal wall of the cylindrical work object, at a point diametrically opposed to the point of contact of said settable pin, means for actuating the indicator in response to movement of said movable pin, two centering pin assemblies independent of each other and mounted in said block on opposite sides of the axis of said movable pin, like calibrated spring biased plungers in each of said assemblies movable on axes coplanar and parallel with and equally spaced from said pin axis, said plungers each having cylinder wall contact members, and means for setting said assemblies axially thereof independently of each other to position said assemblies symmetrical with respect to each other about said pin axis, with said contact members and contact end lying on an arc having a radius coincident with the pin axis.

2. A gage for measuring internal diameters comprising a gage block having an indicator mounted thereon, a settable pin mounted in said block and adapted to contact the internal wall of a cylindrical work object, a movable pin mounted in said block, and aligned with said settable pin, said movable pin having a contact end adapted to contact the internal wall of the cylindrical work object, at a point diametrically opposed to the point of contact of said settable pin, means for actuating the indicator in response to movement of said movable pin, two centering pin assemblies independent of each other and mounted in said block on opposite sides of the axis of said movable pin, like calibrated spring biased plungers in each of said assemblies movable on axes coplanar and parallel with and equally spaced from said pin axis, saidplungers each having cylinder wall ball contact members and conical coaxial seats for centering said balls upon the respective axes of said plungers, and means for setting said assemblies axially thereof independently of each other to position said assemblies symmetrical with respect to each other about said pin axis, with said contact members and contact end lying on an arc having a radius coincident with the pin axis.

3. A gage for measuring internal diameters comprising gage block means having an indicator mounted thereon, a settable pin mounted in said block means and adapted to contact the internal wall of a cylindrical work object, a movable pin mounted in said block means, and aligned with said settable pin, said movable pin ihaving a contact end adapted to contact the internal wall of the cylindrical work object, at a point diametrically opposed tothe point of contact of said settable pin, means for actuating the indicator in response to movement of said movable pin, means4 to limit the movement of said pin between limits less than the range of said indicator, two centering pin assemblies independent of each other and mounted in said block means on opposite sides of the axis of said movable pin, like calibrated spring biased plungers in each of said assemblies movable on axes coplanar and. parallel with and equally spaced from said pin axis, said plungers each having cylinder wall contact members, and means for setting said assemblies axially thereof independently of each other to position said assemblies symmetrical with respect to each other about said pin axis, with said contact members and contact end lying on an arc having a radius coincident with the pin axis.

4. A gage for measuring internal diameters comprising a gage block means having an indicator mounted thereon, a settable pin mounted in said block means and adapted to contact the internal wall of a cylindrical work object, a movable pin mounted in said block means, and aligned with said settable pin, said movable pin having a contact end adapted to contact the internal wall of the cylindrical work object, at a point diametrically opposed to the point of contact of said settable pin, means for actuating the indicator in response to movement of said movable pin, two centering pin assemblies mounted in said block means on opposite sides of the axis of said movable pin, like calibrated spring biased plungers in each of said assemblies movable on axes coplanar and parallel'with and lequally spaced from said pin axis, said plungers eachhaving cylinder wall contact members, and means for setting said assemblies axially-thereof to position said assemblies symmetrical with respect to each other about said pin axis, with said contact members and contact end lying on an arc having a radius coincident with the pin axis, said block means comprising a block having laterally disposed bores for receiving said centering pin assemblies and a bridge member secured to said block, by threaded members simulating said assemblies received in said bores, and having laterally spaced bores in which said centering pin assemblies are disposed.

5. A gage for measuring internal diameters comprising a gage block having an indicator mounted thereon, a settable pin mounted in said block and adapted to contact the internal wall of a cylindrical Work object, a movable pin mounted in said block, and aligned with said settable pin, said movable pin having a contact end adapted to contact the internal wall of the cylindrical work object, at a point diametrically opposed to the point of contact of said settable pin, means for actuating the indicator in response to movement of said movable pin, two centering pin assemblies independent of each other and mounted in said block on opposite sides of the axis of said movable pin having independent yieldingly biased plungers movable on axes coplanar and parallel with and equally spaced from said pin axis, said plungers each having a cylinder wall ball contact member, and conical seats in said plungers for said balls whereby to align said balls with said plunger axes.

6. Gage for measuring internal diameters comprising a gage block having an indicator mounted thereon, a settable pin mounted in said block and adapted to contact the internal wall of a cylindrical work object, a movable pin mounted in said block, and aligned with said settable pin, said movable pin having a contact end adapted to contact the internal Wall of the cylindrical work object, at a point diametrically opposed to the point of contact of said settable pin, means for actuating the indicator in response to movement of said movable pin, two centering pin assemblies independent of each other and mounted in said block on opposite sides of the axis of said movable pin, like calibrated spring biased plungers in each of said assemblies independent of each other and movable on axes coplanar and parallel with and equally spaced from said pin axis, said plungers each having a cylinder wall ball contact member, conical seats for said balls in said plungers for aligning said balls with the axis thereof, and 

